Testing effects of reproduction on stress and mortality

描述（由申请人提供）：本研究将确定一种昆虫模式生物的成虫卵巢对死亡率的直接影响。繁殖至少可以通过两种方式缩短寿命：有限的营养可能被分配给生殖过程而不是躯体，或者繁殖可能对寿命产生与营养分配无关的直接负面影响（例如，释放衰老激素）。热量限制对寿命的影响已经得到了很好的研究。不依赖于营养的生殖的贡献还没有得到很好的理解。在这个项目中，我考察了繁殖对寿命的直接影响模型。该模型假设，当种系组织完好无损时，它直接降低了个体抵抗细胞应激或最小化氧化的能力，从而增加了与营养无关的年龄特异性死亡率。蚱蜢是这种衰老方法的绝佳模型，因为它们足够大，可以跟踪个体和分析多个组织，但寿命较短（大约80天），而且比老鼠便宜。蝗虫繁殖的可塑性很好地表征了；该建议将这些研究扩展到压力耐受性的可塑性和年龄特异性死亡率。目的1将测试切除卵巢的女性是否有更高的热休克蛋白70和超氧化物歧化酶活性的组成水平。直接影响生殖的模型预测了更高的Hsp70水平和超氧化物歧化酶活性。目的2将测试卵巢是否能独立于卵黄形成的营养分配来降低年龄特异性死亡率。生殖对寿命的直接影响模型预测卵巢死亡率随着卵黄形成的减少而降低。目标3将测试卵巢对死亡率的影响是否与营养分配有关。生殖对寿命的直接影响模型预测卵巢效应不通过营养分配起作用。了解衰老的基本生物学对国家的医疗保健至关重要。众所周知，繁殖会缩短寿命，但这种情况是如何独立于营养之外发生的，目前尚不清楚。利用昆虫模型，本研究将在不受营养分布混杂影响的情况下，检验卵巢是否会缩短寿命。卵巢控制应激蛋白和抗氧化剂也将被测试。最后但并非最不重要的是，这笔拨款将对北佛罗里达大学的生物学研究环境产生深远的影响。

DESCRIPTION (provided by applicant): This study will determine the direct effects of the adult ovary on mortality rate in an insect model organism. Reproduction may shorten lifespan in at least two ways: limited nutrients may be allocated to reproductive processes instead of the soma, or reproduction may create direct negative effects on longevity that are independent of nutritional allocation (e.g., release of aging hormones). The effects of calorie restriction on longevity are well studied. The contributions of reproduction that are independent of nutrition are not well understood. In this project, I examine the model of direct effects of reproduction on longevity. This model posits that when germ-line tissue is intact it directly reduces the individual's ability to resist cellular stress or minimize oxidation, thereby increasing age-specific mortality rate independently of nutrition. Grasshoppers are excellent models for this approach to aging because they are large enough for tracking individuals and analyzing multiple tissues, but are shorter-lived (approximately 80 days) and cheaper than mice. Plasticity of reproduction in grasshoppers is well characterized; this proposal extends these studies to plasticity of stress tolerance and age-specific mortality. Aim #1 will test whether ovariectomized females have higher constitutive levels of heat shock protein 70 and superoxide dismutase activity. The model of direct effects on reproduction predicts higher Hsp70 levels and superoxide dismutase activities. Aim #2 will test whether the ovary decreases age-specific mortality rate independently of nutritional allocation to vitellogenesis. The model of direct effects of reproduction on longevity predicts the ovary will decrease mortality rate with decreasing vitellogenesis. Aim #3 will test whether ovarian effects on mortality rate are linked to nutrient allocation. The model of direct effects of reproduction on longevity predicts that ovarian effects do not act through nutritional allocation. Understanding the basic biology of aging is critical to the health care of the nation. Reproduction is known to reduce longevity, but how this can occur independently of nutrition is not clear. Using an insect model, this proposal will examine whether the ovary decreases life-span, without the confounding affects of nutritional distribution. Ovarian control of stress proteins and anti-oxidants will also be tested. Last but not least, this grant will have a profound effect on the research environment in biology at the University of North Florida.